Acquired cystic kidney disease (ACKD) can be developed duringchronic renal insufficiency. The probability of developing cysticdiseases rises with the increase of time in dialysis [1]. Menand African-American population are more likely to develop ACKD.Also, kidney volumes are bigger and cyst size increases fasterin this population [1,2]. Typical complications of ACKD areintra- and pericystic bleeding as well as rupture with retroperitonealhaemorrhage. Patients with ACKD also present a higher risk ofmalignant transformation. Haemoperitoneum is an unusual complicationin patients undergoing peritoneal dialysis (PD), most casesbeing attributed to mechanical, gynaecological or intraperitoneal  相似文献   
28.
Automation of pharmaceutical dissolution testing by flow injection analysis     
M D Luque de Castro  M Valcárcel 《Journal of pharmaceutical and biomedical analysis》1990,8(4):329-336
The different types of instruments used for monitoring pharmaceutical dissolution testing are presented. Their features and the need for automation are critically discussed. The advantages of flow injection analysis in this respect are illustrated by a variety of examples clearly showing its adaptability to the different problems posed by other automatic and non-automatic alternatives.  相似文献   
29.
30.
[首页] « 上一页 [1] [2] 3 [4] [5] [6] [7] [8] [9] [10] [11] 下一页 » 末  页»
  首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   16376篇
  免费   909篇
  国内免费   75篇
耳鼻咽喉   194篇
儿科学   401篇
妇产科学   331篇
基础医学   2222篇
口腔科学   586篇
临床医学   1341篇
内科学   4034篇
皮肤病学   408篇
神经病学   1217篇
特种医学   316篇
外科学   2153篇
综合类   85篇
现状与发展   1篇
一般理论   7篇
预防医学   1630篇
眼科学   229篇
药学   1115篇
中国医学   59篇
肿瘤学   1031篇
  2023年   110篇
  2022年   258篇
  2021年   507篇
  2020年   293篇
  2019年   534篇
  2018年   608篇
  2017年   350篇
  2016年   400篇
  2015年   435篇
  2014年   610篇
  2013年   744篇
  2012年   1132篇
  2011年   1259篇
  2010年   669篇
  2009年   595篇
  2008年   919篇
  2007年   974篇
  2006年   930篇
  2005年   894篇
  2004年   745篇
  2003年   698篇
  2002年   619篇
  2001年   288篇
  2000年   353篇
  1999年   286篇
  1998年   126篇
  1997年   103篇
  1996年   65篇
  1995年   74篇
  1994年   76篇
  1993年   61篇
  1992年   131篇
  1991年   140篇
  1990年   127篇
  1989年   125篇
  1988年   96篇
  1987年   92篇
  1986年   84篇
  1985年   94篇
  1984年   57篇
  1983年   49篇
  1980年   36篇
  1979年   59篇
  1978年   63篇
  1977年   32篇
  1975年   51篇
  1974年   61篇
  1973年   47篇
  1972年   36篇
  1970年   33篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
This study aimed to determine whether a weight-adjusted dose of subcutaneous enoxaparin is as effective and safe as oral acenocoumarol for the secondary prophylaxis of pulmonary embolism. Three hundred and eighty consecutive noncancer outpatients hospitalized with an episode of symptomatic pulmonary embolism selected treatment with acenocoumarol or enoxaparin at a dose of 1 mg/kg once daily after being informed of the type of administration and expected frequency of laboratory monitoring for both medicinal products. Endpoints were symptomatic recurrent thromboembolic events evaluated by standard objective testing, and a composite endpoint of recurrent venous thromboembolism, major bleeding, and death from any cause. One hundred and ninety-nine patients (52%) chose acenocoumarol therapy and 181 chose enoxaparin monotherapy. Four patients in the enoxaparin group (2.2%) and six patients in the acenocoumarol group (3%) had an objective thromboembolic recurrence (hazard ratio, 1.35; 95% confidence interval, 0.38-4.79; P = 0.64). Nine patients in the enoxaparin group (5.0%) had a hemorrhagic complication compared with 11 in the acenocoumarol group (5.5%) (P = 0.81). The hospital length of stay was shorter with enoxaparin compared with acenocoumarol (11 versus 16 days, P = 0.0001). Enoxaparin is as effective and safe as acenocoumarol in the secondary prevention of recurrent thromboembolic disease and is associated with shorter hospitalization.  相似文献   
22.
PURPOSE: Current treatment for febrile neutropenia (FN) includes hospitalization for evaluation, empiric broad-spectrum antibiotics, and other supportive care. Clinical trials have reported conflicting results when studying whether the colony-stimulating factors (CSFs) improve outcomes in patients with FN. This Cochrane Collaboration review was undertaken to further evaluate the safety and efficacy of the CSFs in patients with FN. METHODS: An exhaustive literature search was undertaken including major electronic databases (CANCERLIT, EMBASE, LILACS, MEDLINE, SCI, and the Cochrane Controlled Trials Register). All randomized controlled trials that compare CSFs plus antibiotics versus antibiotics alone for the treatment of established FN in adults and children were sought. A meta-analysis of the selected studies was performed. RESULTS: More than 8,000 references were screened, with 13 studies meeting eligibility criteria for inclusion. The overall mortality was not influenced significantly by the use of CSF (odds ratio [OR] = 0.68; 95% CI, 0.43 to 1.08; P = .1). A marginally significant result was obtained for the use of CSF in reducing infection-related mortality (OR = 0.51; 95% CI, 0.26 to 1.00; P = .05). Patients treated with CSFs had a shorter length of hospitalization (hazard ratio [HR] = 0.63; 95% CI, 0.49 to 0.82; P = .0006) and a shorter time to neutrophil recovery (HR = 0.32; 95% CI, 0.23 to 0.46; P < .00001). CONCLUSION: The use of the CSFs in patients with established FN caused by cancer chemotherapy reduces the amount of time spent in hospital and the neutrophil recovery period. The possible influence of the CSFs on infection-related mortality requires further investigation.  相似文献   
23.
This study investigates whether tissue recoil or patient intrinsic factors influence the final position of the nipple areola complex (NAC) after reduction mammoplasty. The age, pre-operative ptosis, BMI and weight of the tissue resected were recorded as patient intrinsic factors in 37 patients undergoing reduction mammoplasty. The “spring-back” value was defined as the distance from the sternal notch to a nipple landmark on the breast meridian with the patient sitting up, minus the same measurement repeated with the patient recumbent to eliminate the pull of gravity on the breast. Spring back was measured pre-operatively for the nipple and nipple mark then post-operative for the nipple. The difference in centimeters between the final post-operative distance from the sternal notch to the nipple and the level intended by the pre-operative nipple mark was termed the “judgment error.” The final position of the post-operative nipple and the judgment error was compared to the spring-back values and patient intrinsic factors. Pre-operative ptosis was statistically related to increasing patient BMI and mass of tissue resected per breast. Pre-operative spring-back values for the nipple increased with increasing ptosis, BMI and decreasing age. Spring-back values were greater in the lower pole of the breast than in the upper pole. The final position of the nipple was higher than the pre-operative mark in 65% of cases, lower in 8% and as marked in 27% of cases. The post-operative NAC was, on average, 0.6 cm higher than planned pre-operatively. The post-operative distance from the sternal notch to the nipple increased with increasing pre-operative ptosis, mass of breast tissue resected per breast and all three spring-back values. The difference between the level of the pre-operative mark and the final nipple position showed a weak correlation with post-operative spring-back values. The parameters of ptosis, BMI, weight of tissue resected per breast and pre-operative nipple spring back reflect body habitus and breast size. Spring-back values vary between the upper and lower pole of the breast. The final NAC position was higher than that intended at pre-operative marking in the majority of cases. The surgeon instinctively marks the nipple lower in patients with greater pre-operative ptosis and in whom a larger resection is anticipated. Judgment error did not relate to intrinsic factors nor to pre-operative spring-back values; hence, these parameters cannot be applied as predictive tools for more accurate pre-operative marking of the nipple position. This study suggests that the pre-operative nipple mark should be placed, with the patient sitting up, at least 23 cm from the sternal notch and 0.6 cm lower than the final position estimated using the inframammary crease as a landmark. An invited commentary on this paper is available at .  相似文献   
24.
Hyper-IgM syndrome with CHARGE association   总被引:1,自引:0,他引:1  
A girl with coloboma of the iris, sensorineural deafness, growth delay, distinctive face, and cranial nerve dysfunction was diagnosed of CHARGE association in the first year of life. She presented with repeated otitis. At 3 yr of age, the patient suffered a septicemia ( Streptococcus pneumoniae , Corynebacterium sp.). The immunoglobulin G (IgG) and IgA serum levels were decreased, IgM increased and cellular immunity parameters were normal, supporting the diagnosis of hyper-IgM (HIM) syndrome. The sequence of CD40 ligand and cytidine deaminase genes were normal. From then on, she was receiving immunoglobulin intravenously with an excellent outcome . Here, we report the first case of CHARGE association and HIM syndrome in the same patient. Although the cause could not be identified, a non-random link is likely.  相似文献   
25.
This is an unusual case presentation of a young woman with a clinical history and course simulating juvenile hyaline fibromatosis, but without hyalinization in the stroma. Because of the age of onset, the apparent familial inheritance, the nonaggressive and nonregressive tumor traits, the disease cannot be classified as multicentric fibromatosis. Therefore, we are referring to this case as multicentric fibromatosis with familial inheritance, a previously unreported entity to our knowledge.  相似文献   
26.
Pituitary metastases of solid tumours are infrequent, specially as a first manifestation. When they happen, they are usually due to breast or lung cancer and are asymptomatic or produce diabetes insipidus. It is very strange that they produce hormonal deficiency. We present a case report of a bronchogenic adenocarcinoma in a 65-year-old man which began with panhypopituitarism, diabetes insipidus and visual alterations. Magnetic resonance imaging revealed a large sellar mass, with clivus infiltration and invading the right cavernous sinus. The biopsy result was adenocarcinoma metastases from lung cancer.  相似文献   
27.
   Introduction
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号